At first glance you probably wouldn't think this is a comb
jelly. Although resembling a hydromedusa, the short, whitish comb rows reveal its
true affiliation. The body is shaped like the bell of a medusa and may be up to 15
cm diameter, but usually more like 2 to 3 cm in central California waters. A central
cone-shaped peduncle holds the mouth slit. A pair of small tentacles hang from the
sides of the peduncle. With its transparent, colorless body, this comb jelly is
usually very difficult to see. In a manner similar to lobate comb jellies, Thalassocalyce
holds the "bell" wide open to capture zooplankton prey. The bell contracts
when bringing captured prey to the mouth or following a disturbance. Compared to
other comb jellies, this species has limited swimming ability. It is an occasional
visitor to central California waters, particularly during periods in the fall when warmer
oceanic waters invade nearshore areas. Thalassocalyce
is also known from
surface and midwater habitats in the Atlantic Ocean and Mediterranean Sea.
All photographs © David
Wrobel and may not be used or copied without permission!